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OBJECTIVE: To investigate whether baculoviral inhibitor of apoptosis (IAP) repeat containing 5 gene (BIRC5) polymorphisms are associated with the development and clinical phenotypes of ischemic stroke in Korea population. METHODS: We enrolled 121 ischemic stroke patients and 291 control subjects. Ischemic stroke patients were divided into subgroups according to the scores of National Institutes of Health Stroke Survey (<6 or ≥6) and Modified Barthel Index (<60 or ≥60). Single nucleotide polymorphisms (SNPs) of BIRC5 (rs3764383 and rs2071214) were selected and genotyped by direct sequencing for all subjects. Multiple logistic regression models (codominant 1 and 2, dominant, recessive, overdominant and log-additive) were used to estimate odds ratios (ORs), 95% confidence intervals (CIs), and p-values. RESULTS: In analysis of stroke susceptibility, the genotype and allele frequencies of rs3764383 exhibited no difference between the control group and the ischemic stroke group. SNP rs2071214 was associated with ischemic stroke in the codominant (p=0.003), dominant (p=0.002), overdominant (p=0.005), and log-additive (p=0.008) models, respectively. The G allele frequency of rs2071214 was significantly (p=0.009) associated with susceptibility for ischemic stroke (OR, 1.57; 95% CI, 1.12-2.21). However, in the analysis for clinical phenotype, no SNP of the BIRC5 gene was found to be associated with ischemic stroke. CONCLUSION: These results suggest that a missense SNP (rs2071214) of BIRC5 may be associated with the development of ischemic stroke in the Korean population.

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OBJECTIVE: To investigate whether baculoviral inhibitor of apoptosis (IAP) repeat containing 5 gene (BIRC5) polymorphisms are associated with the development and clinical phenotypes of ischemic stroke in Korea population. METHODS: We enrolled 121 ischemic stroke patients and 291 control subjects. Ischemic stroke patients were divided into subgroups according to the scores of National Institutes of Health Stroke Survey (<6 or ≥6) and Modified Barthel Index (<60 or ≥60). Single nucleotide polymorphisms (SNPs) of BIRC5 (rs3764383 and rs2071214) were selected and genotyped by direct sequencing for all subjects. Multiple logistic regression models (codominant 1 and 2, dominant, recessive, overdominant and log-additive) were used to estimate odds ratios (ORs), 95% confidence intervals (CIs), and p-values. RESULTS: In analysis of stroke susceptibility, the genotype and allele frequencies of rs3764383 exhibited no difference between the control group and the ischemic stroke group. SNP rs2071214 was associated with ischemic stroke in the codominant (p=0.003), dominant (p=0.002), overdominant (p=0.005), and log-additive (p=0.008) models, respectively. The G allele frequency of rs2071214 was significantly (p=0.009) associated with susceptibility for ischemic stroke (OR, 1.57; 95% CI, 1.12-2.21). However, in the analysis for clinical phenotype, no SNP of the BIRC5 gene was found to be associated with ischemic stroke. CONCLUSION: These results suggest that a missense SNP (rs2071214) of BIRC5 may be associated with the development of ischemic stroke in the Korean population.

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PURPOSE: Survivin inhibits apoptosis and enables tumor cells to escape from therapy induced senescence. High survivin expression is associated with bladder cancer aggressiveness and recurrence. We evaluated whether survivin expression is reduced by siRNA and whether survivin silencing would enhance mitomycin C activity in human RT4 bladder transitional cell tumors in vitro and in vivo. MATERIALS AND METHODS: We assessed the effectiveness of siRNA therapy using 2 newly developed pegylated cationic liposome carriers, PCat and PPCat. Each has a fusogenic lipid to destabilize the endosomal membrane. PPCat further contains paclitaxel to enhance in vivo delivery and transfection of survivin siRNA. In vitro antitumor activity was evaluated by short-term MTT and long-term clonogenicity cytotoxicity assays. In vivo intravenous therapy was assessed in mice bearing subcutaneous tumors. RESULTS: Nontarget siRNA showed no antitumor activity in vitro or in vivo. Treatment of cultured cells with mitomycin C at a 50% cytotoxic concentration enhanced survivin mRNA and protein levels. Adding PPCat or PCat containing survivin siRNA reversed survivin induction and enhanced mitomycin C activity (p <0.05). In tumor bearing mice single agent mitomycin C delayed tumor growth and almost tripled the survivin protein level in residual tumors. Adding PPCat-survivin siRNA, which alone resulted in a minor survivin decrease of less than 10%, completely reversed mitomycin C induced survivin and enhanced mitomycin C activity (p <0.05). CONCLUSIONS: Results indicate that there is effective in vivo survivin silencing and synergism between mitomycin C and PPCat-survivin siRNA. This combination represents a potentially useful chemo-gene therapy for bladder cancer.

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BACKGROUND: Overexpression of survivin, a member of the inhibitors of apoptosis protein, has been reported in various carcinomas, and its interaction with cyclooxygenase 2 (COX-2) results in accelerated tumor progression. The purpose of this study is to investigate the immunohistochemical expression of survivin and COX-2 in benign and malignant thyroid tissues and to define its association with pathologic and clinical features. METHODS: We examined expression of survivin and COX-2 by immunohistochemistry in 334 benign and malignant thyroid tissues and evaluated their clinical significance. RESULTS: Expression of survivin showed an increase along the spectrum of thyroid carcinoma progression; rarely positive in adenomatous goiter, moderately positive in papillary carcinoma, and strongly positive in anaplastic carcinoma (AC). Papillary microcarcinoma revealed the highest COX-2 positivity and AC demonstrated the lowest positivity among thyroid cancers. Node negative carcinomas showed higher COX-2 expression than node positive tumors. Survivin expression did not correlate with COX-2. CONCLUSIONS: Our findings suggest that survivin overexpression may be related to the pathogenesis of AC and can be a predictor of disease progression. COX-2 may be involved in the early phase of thyroid carcinoma.

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BACKGROUND: Overexpression of survivin, a member of the inhibitors of apoptosis protein, has been reported in various carcinomas, and its interaction with cyclooxygenase 2 (COX-2) results in accelerated tumor progression. The purpose of this study is to investigate the immunohistochemical expression of survivin and COX-2 in benign and malignant thyroid tissues and to define its association with pathologic and clinical features. METHODS: We examined expression of survivin and COX-2 by immunohistochemistry in 334 benign and malignant thyroid tissues and evaluated their clinical significance. RESULTS: Expression of survivin showed an increase along the spectrum of thyroid carcinoma progression; rarely positive in adenomatous goiter, moderately positive in papillary carcinoma, and strongly positive in anaplastic carcinoma (AC). Papillary microcarcinoma revealed the highest COX-2 positivity and AC demonstrated the lowest positivity among thyroid cancers. Node negative carcinomas showed higher COX-2 expression than node positive tumors. Survivin expression did not correlate with COX-2. CONCLUSIONS: Our findings suggest that survivin overexpression may be related to the pathogenesis of AC and can be a predictor of disease progression. COX-2 may be involved in the early phase of thyroid carcinoma.

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Survivin, a member of the inhibitors of apoptosis protein family, is expressed during development and in various human cancers. However, the clinical relevance of survivin in cancer is still a matter of debate. Genes induced by hepatocyte growth factor (HGF) were screened using cDNA microarray technology in the stomach cancer cell lines, NUGC3 and MKN28. The levels of JunB, survivin, and uro-plasminogen activator (uPA) were up-regulated in cells treated with HGF in a dose-dependent manner. HGF-induced up regulation of JunB, survivin, and uPA was inhibited by pre-treatment with a MEK inhibitor (PD 98059). HGF-induced up-regulation of uPA was repressed by survivin knockdown. HGF enhanced the binding activity of JunB to the survivin promoter in control cells, but not in the JunB-shRNA cells. Transfection with survivin-shRNA resulted in a decrement of cell proliferation, as determined with MTT assays. In an in vitro invasion assay, significantly fewer cells transfected with survivin shRNA than control cells were able to invade across a Matrigel membrane barrier. In conclusion, survivin appeared to play an important role in the up-regulation of uPA induced by HGF via JunB and might contribute to HGF-mediated tumor invasion and metastasis, which may serve as a promising target for gastric cancer therapy.

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BACKGROUND: pAkt (the phosphorylated form of the proto-oncogene protein c-akt) and survivin (human BIRC5 protein) are candidate apoptosis-related molecules that may be responsible for cancer progression. The aim of this study was to determine the expression of pAkt and survivin in malignant stomach neoplasm, and their value as prognostic indicators of cancer. METHODS: The expression of pAkt and survivin in 144 cases of gastric cancer was detected by immunohistochemistry and compared with established clinicopathological parameters and prognosis of this disease. RESULTS: Expression of pAkt showed significant correlations with depth of invasion, lymph node and distant metastasis, as well as the stage (p < 0.05 for all three correlations), but not with the Lauren classification. Survivin expression closely correlated with histological type, Lauren classification, depth of invasion, metastasis, and stage (p < 0.05 for all). The overall survival of patients with pAkt/survivin expression was inferior to that of patients with loss of pAkt/survivin expression. Cox multivariate analysis demonstrated a significant correlation between stage (p = 0.04), survivin expression (p = 0.02), and prognosis. CONCLUSIONS: Patients with pAkt/survivin expression in gastric cancer are at increased risk of cancer-related mortality via the apoptosis resistance pathway. Expression of pAkt and survivin could be used as a prognostic indicator for gastric cancer.

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BACKGROUND: Survivin, a novel antiapoptotic gene has been linked with tumor development and progression in various human carcinomas including gastric carcinomas. The aim of this study was to evaluate the expression of survivin in gastric carcinoma and its correlation with tumor cell proliferation and apoptosis. METHODS: Expression of survivin was evaluated immunohistochemically in 84 surgically resected gastric carcinomas. Tumor cell apoptosis was evaluated with terminal deoxynucleotidyl transferase (TdT) mediated deoxyuridine triphosphate (dUTP) nick-end labeling (TUNEL), and Ki-67 immunostaining was used for evaluation of tumor cell proliferation. RESULTS: Expression of survivin was noted in 53.6% of the gastric carcinomas, and was significantly associated with depth of invasion, status of lymph node metastasis or tumor stage (p=0.022, 0.034, 0.040, respectively). There was an inverse correlation between survivin expression and apoptotic index (p=0.015). But there was no significant correlation between survivin expression and Ki-67 labeling index (p=0.430). CONCLUSIONS: These results suggest that survivin expression may contribute to tumor development and progression by inhibiting apoptosis in human gastric carcinoma.

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PURPOSE: The prognostic value of p53 remains controversial in transitional cell carcinomas of the bladder. Survivin, an inhibitor of apoptosis, is expressed in many human cancers. Recent studies have reported increased expression of survivin in superficial transitional cell carcinomas of the bladder. We investigated the expression of survivin and p53 and the clinical implications of this expression in superficial transitional cell carcinomas of the bladder. MATERIALS AND METHODS: Immunohistochemical staining of paraffin sections using a monoclonal antibody for survivin and p53 was performed in 82 cases of superficial transitional cell carcinomas of the bladder. Correlations between the expression of survivin and p53 and clinicopathological features, such as age, multiplicity of tumor, size, recurrence, and progression, were examined. RESULTS: Among 82 cases, positive survivin expression (greater than 20%) was observed in 59 cases. Positive p53 expression (greater than 20%) was observed in 46 cases. There were no significant differences in age, gender, multiplicity, tumor size, tumor grade, pT stage, recurrence, or progression-free survival between p53-positive and p53-negative groups (p>0.05). Also, there were no significant differences in age, gender, multiplicity, tumor size, tumor grade, or pT stage between survivin-positive and survivin-negative groups (p>0.05). However, recurrent-free and progression-free survivals were significantly lower in the survivin-positive group than in the survivin-negative group (p<0.05). CONCLUSIONS: The expression of survivin can be recommended as a useful marker for predicting disease recurrence and progression. Survivin may be superior to p53 as a prognostic factor in superficial transitional cell carcinoma of bladder.

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TNF-related apoptosis-inducing ligand (TRAIL) has been proposed as a promising cancer therapy that preferentially induces apoptosis in cancer cells, but not most normal tissues. However, many cancers are resistant to TRAIL by mechanisms that are poorly understood. In this study, we showed that tunicamycin, a naturally occurring antibiotic, was a potent enhancer of TRAIL-induced apoptosis through downregulation of survivin. The tunicamycin-mediated sensitization to TRAIL was efficiently reduced by forced expression of survivin, suggesting that the sensitization was mediated at least in part through inhibition of survivin expression. Tunicamycin also repressed expression of cyclin D1, a cell cycle regulator commonly overexpressed in thyroid carcinoma. Furthermore, silencing cyclin D1 by RNA interference reduced survivin expression and sensitized thyroid cancer cells to TRAIL; in contrast, forced expression of cyclin D1 attenuated tunicamycin-potentiated TRAIL-induced apoptosis via over-riding downregulation of survivin. Collectively, our results demonstrated that tunicamycin promoted TRAIL-induced apoptosis, at least in part, by inhibiting the expression of cyclin D1 and subsequent survivin. Of note, tunicamycin did not sensitize the differentiated thyroid epithelial cells to TRAIL-induced apoptosis. Thus, combined treatment with tunicamycin and TRAIL may offer an attractive strategy for safely treating resistant thyroid cancers.

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TNF-related apoptosis-inducing ligand (TRAIL) has been proposed as a promising cancer therapy that preferentially induces apoptosis in cancer cells, but not most normal tissues. However, many cancers are resistant to TRAIL by mechanisms that are poorly understood. In this study, we showed that tunicamycin, a naturally occurring antibiotic, was a potent enhancer of TRAIL-induced apoptosis through downregulation of survivin. The tunicamycin-mediated sensitization to TRAIL was efficiently reduced by forced expression of survivin, suggesting that the sensitization was mediated at least in part through inhibition of survivin expression. Tunicamycin also repressed expression of cyclin D1, a cell cycle regulator commonly overexpressed in thyroid carcinoma. Furthermore, silencing cyclin D1 by RNA interference reduced survivin expression and sensitized thyroid cancer cells to TRAIL; in contrast, forced expression of cyclin D1 attenuated tunicamycin-potentiated TRAIL-induced apoptosis via over-riding downregulation of survivin. Collectively, our results demonstrated that tunicamycin promoted TRAIL-induced apoptosis, at least in part, by inhibiting the expression of cyclin D1 and subsequent survivin. Of note, tunicamycin did not sensitize the differentiated thyroid epithelial cells to TRAIL-induced apoptosis. Thus, combined treatment with tunicamycin and TRAIL may offer an attractive strategy for safely treating resistant thyroid cancers.

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The role of mast cells in tumor growth is still controversial. In this study we analyzed the effects of both histamine and pre-formed mediators spontaneously released by mast cells on the growth of two human hepatocellular carcinoma cell lines, HA22T/VGH and HuH-6, with different characteristics of differentiation, biological behavior and genetic defects. We showed that total mast cell releasate, exocytosed granules (granule remnants) and histamine reduced cell viability and proliferation in HuH-6 cells. In contrast, in HA22T/VGH cells granule remnants and histamine induced a weak but significant increase in cell growth. We showed that both cell lines expressed histamine receptors H1 and H2 and that the selective H1 antagonist terfenadine reverted the histamine-induced inhibition of HuH-6 cell growth, whereas the selective H2 antagonist ranitidine inhibited the histamine-induced cell growth of HA22T/VGH cells. We demonstrated that histamine down-regulated the expression of beta-catenin, COX-2 and survivin in HuH-6 cells and that this was associated with caspase-3 activation and PARP cleavage. On the contrary, in HA22T/VGH cells expression of survivin and beta-catenin increased after treatment with granule remnants and histamine. Overall, our results suggest that mediators stored in mast cell granules and histamine may affect the growth of liver cancer cells. However, mast cells and histamine may play different roles depending on the tumor cell features. Finally, these data suggest that histamine and histamine receptor agonists/antagonists might be considered as "new therapeutic" drugs to inhibit liver tumor growth.

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